Yarn tensioning means for twisters



5, 1 5 c. B. KINGSBURY 2,662,364

YARN TENSIONING MEANS FOR TWISTERS Filed Sept. 29, 1949 INVEN TOR. B. Kwssawzm Patented Dec. 15, 1953 YARN TENSIONIN G MEANS FOR TWISTERS Chadwick B. Kingsbury, Elizabethton, Tenn., as-

signor to North American Rayon Corporation, New York, N. Y., a corporation of Delaware Application September 29, 1949, Serial No. 118,645

9 Claims.

This invention relates to improvements in twisting machines and more particularly to twisting spindles of the type adapted to impart two twists to the yarn, thread, or the like for each revolution of the spindle and wherein the yarn or thread undergoing twist is subjected to suitably controlled tension through agency of a physical force. such as pressure, exerted on the yarn by a suitable member during the operation of the spindle.

A rimary obiect of the invention is to utilize the flow of air drawn through the spindle, as a result of the high speed rotation of an operative portion thereof, as a means for controlling the tension applied to the yarn during the operation of the spindle.

Another object is to utilize such flow of air either as a sole and direct means for controll ng the tension or in suitable association with other tensioning means provided on the spindle.

To this end the flow of air is caused, by suitable arrangements, to manifest itself as a pressure differential exerted at certa n portions of the spindle and more particularly as a suction effect capable of being utilized as a force for controlling the tension applied to the yarn.

In twisting spindles of the double twist type, wherein two twists are imparted to the yarn for each revolution of the spindle, the driven portion of the spindle per se rotates at high speed but the yarn package from which the yarn is drawn remains stationary. The spindle is hollow and the yarn withdrawn from the package enters at the top, passes downwardly through the center of the spindle, emerges from a port in a storage wheel at the lower end end then travels up, outwardly around, and in spaced relation to the yarn package, forming a so-called balloon. The twisted thread thence passes to a suitable take-up device to form the finished package. The format on of the balloon and its size depends on a number of factors such as the rotational speed of the spindle, the thread take-up speed, and the denier of the yarn undergoing twist. If the balloon is of the free balloon type such as is commonly used in spindles of this type in contradistinction to the restricted type used elsewhere in the art, it serves to exert a uniform pull on the delivered yarn or thread which in turn insures uniform density of the take-up I package. In order to balance the pull exerted by the balloon on the supply package, an adjustable braking or tensioning means must be disposed in the path traveled by the yarn on its way from the supply package to the ballooning zone.

It is therefore customary in double twist spindles where a free balloon is formed, to provide a tensioning means at or near the point where the yarn drawn from the supply package enters the central bore of the hollow spindle. Such a tensioning means may comprise a weight. usually constituted as a disk-like member reposing upon a support surface on the spindle, the yarn being caused to pass between the weight and said surface before entering the bore. An example of a spindle utilizing such a braking or tensioning means is shown in the U. S. Patent No. 2,478,925 of August 16, 1949, to Chadwick B. Kinsbury. In such cases the braking effect and therefore the tension exerted on the yarn by the weight or disk-like member is regulated in various ways. In the arrangement disclosed in the aforesaid patent it is regulated by constituting the disk of magnetically responsive material and pulling it down against the yarn through a ency of a magnet, suitable means being provided to adjust the intensity of the magnetic pull exerted on the disk.

Double twist spindles of the type described above are operated at very high speeds, e. g. 5000 to 10,000 R. P. M. An important element of such a spindle is the so-called rotor or thread storage wheel at the lower portion of the spindle. This storage wheel or rotor is of importance in that it serves to impart a certain degree of tension to the yarn, supplementary to that imparted by other tensioning devices disposed elsewhere in the spindle, for example the disk hereinbefore mentioned.

The storage wheel or rotor is provided with several passages extending radially therethrough and at right angles to the vertical central bore of the spindle and these passages terminate in ports distributed peripherally about the wheel. The passages communicate with the central bore of the spindle and the yarn passes from the supply package down through the central bore, thence through one of the radial passages in the rotor, and emerges from the respective peripheral port in the rotor. Although only one passage of the rotor is actually used for con veying the yarn during the operation of the spindle, a number of them must be provided to facilitate threading-up of the spindle preparatory to operation.

The necessary presence of these passages and ports however causes the rotor to act as a suction-producing turbine or blower, so that, due to its high rotational speed, it draws a relatively powerful stream of air through the spindle. In the usual spindle of this type the structural parts disposed above the rotor are assembled in frictionally fitting relation without any attempt to provide definite air flow passages. The air drawn through the spindle by the rotor therefore enters the spindle from all directions and at all points of the latter as well as through the yarn package and is exhausted by the rotor. However if a suitable non-leaking continuous passage is provided within the spindle and connected with the rotor, the latter can be adapted to draw air solely through such passage. This flow of air, if restricted by an obstruction, causes a pressure differential to exist on the two sides of the obstruction inasmuch as the atmosphere acts against one side of the obstruction and the suction produced by the rotor against the other. The suction effect thus produced is of sutdcient magnitude to exert a considerable degree of force if properly utilized.

In accordance with the present invention the flow of air through a continuous non-leaking bore in the sp ndle, manifested in the form of a pressure diiferential or suction, is utilized for controlling the tension exerted on the yarn at its entry into the bore of the spindle. Various mechanical arrangements may be employed for utilizing this suction as a controllable source of power for actuating a suitable yarn tensioning device. In a preferred and simple embodiment of the invention however the air flow restricting member is constituted as the yarn tensioning means per se. To this end the yarn tensioning means is constituted as a disk-like member disposed at the top of the spindle in a manner similar to that shown in U. 8. Patent No. 2478,926, referred to above, and the pressure differential created on the two sides of said member, more simply considered as a suction acting against the bottom thereof, is utilized as a means for causing the disk to exert a braking action on the yarn. Means are also provided for modifying the flow of air and hence the pressure differential or degree of suction produced so as to regulate the tensioning action of the disk. Additionally, the arrangement may be used alone or in association with and supplementary to the magnetic tension control arrangement disclosed in U. S. Patent 2,478,926.

An embodiment example of the invention is shown in the accompanying drawing where:

Fig. l is a side elevation, partly in section of a double twist spindle provided with a suctionoperated tension ng means and showing means for adjusting the flow of air.

Fig. 2 is a view along line 2-2 of Fig. 1 showing a top view of the air flow regulating means.

Fig. 3 illustrates an embodiment of a tensioncxerting member suitable for use with the suction-operated system shown in Figs. 1 and 2.

In the drawing the invention is shown applied by way of illustrative but non-limiting example to a double twist spindle of the type described in U. S. Patent 2,478,926 referred to above. However, the invention is not limited to this type of spindle and may be applied to spindles of other types where a member rotating at high speed produces a flow of air of sufficient strength to permit it to be used for operating or controlling a yarn tensioning means associated with the spindle.

Referring in detail to the figures of the drawing, l indicates the rotating portion of the spindle mounted for rotation in suitable bearings on an angle arm 2 pivoted at 3 to a stationary bracket i attached to the spinning machine so as to tilt substantially as shown. The spindle driving system includes belt 5 and idler pulley 6 carried by rail 7. The numeral 8 indicates a suitable manually operated brake actuated by handle 9.

The supply package from which the yarn is drawn is indicated at 0 and its sleeve-like spool, which is foraminous or perforated, by H. The package is carried by the bowl l2 and the frustoconical member l3 at the top. In this type of spindle the supply package I0, spool H, bowl l2 and member l3 do not rotate although, considered as a unit, they may gyrate occasionally, a counterweight 42 within the spindle serving to hold the structure relatively stationary. The non-rotating internal structure of the spindle includes the central pedestal l4 constituting an integral portion of the bowl [2 and which is supported on bearings diagrammatically indicated at [5, [6 arranged to permit the spindle portion per se, i. to rotate without carrying the bowl l2 and pedestal i4 along with it. 45 is an inverted cup forming part of the internal structure. Tightly secured to the pedestal M as by screw threads 46 or otherwise is an upwardly extending member ll having a central bore l8 and external strengthening flutes 44. The frustoconical member [3 which rests upon the top of the yarn package II] has an internal, downwardly extending centrally hollow portion 19 which is frictionally fitted in air sealing fashion to the upper end of member I! as through agency of a rubber gasket 20, the seating of member 13 being limited by a flange-like shoulder 2| on member [1. The top of the frusto-conical member l3 carries an insert 2| made of non-magnetic material such as a suitable stainless steel. Insert 2! has a fiat top provided with a relatively small central yarn entry bore and an internal chamber larger than said bore. A suitable yarn tensioning or braking member reposes on the top of insert 2i. This tensioning member is constituted, for example as shown in Fig. 3, as a lightweight disk 22 provided with an upwardly extending flange of rounded lateral contour 23 and a stem 24 which, when in use, extends down and fits loosely in the central bore of insert 2|. This arrangement is the same as that disclosed in U. S. Patent 2,478,926 referred to above. If the arrangement of the present invention is to be used in conjunction with the spindle shown in the aforesaid patent the disk is made of magnetically responsive material such as a suitable iron alloy capable of being attracted by an annular magnet 25 housed within the insert 2|. Further as disclosed in the aforesaid patent a variable number of removable non-magnetic centrally hollow shims 26 may be disposed above the magnet 25 to adjust the pull on the disk exerted by the magnet. A spring 2'! and a hollow spacer 28 serve to hold the magnet and shims in place in the chamber of insert 2!. However, if the yarn tension is to be controlled solely by the arrangement of the present invention as hereinafter described, the magnet 25 may be omitted, or, if allowed to remain, a disk of nonmagnetic material may be used. During the operation of the twisting spindle, yarn 33 drawn from the supply package I0 passes in the direction of arrow 34 beneath the tensioning disk 22, down past the loosely fitting stem 24, through the central bore of the spindle and out through the passage 30 in rotor 29. It then passes upwardly as indicated by arrow 35, and, as it whirls around the outside of the spindle it forms the so-called yarn balloon diagrammatically represented in the drawing by the line 36 as if stroboscopically viewed or frozen in space. The yarn then passes through a gathering eye or the like (not shown) at point 31 and thence to a take-up package. The disk 22 exerts a pressure on the I it yarn entering the bore in the insert 2| at the top of the spindle and hence serves to tension the yarn. If magnetic means are also used for controlling the tension, the pull on the disk 22 exerted by the magnet 25 would be adjusted by inserting a suitable number of non-magnetic shims 25 as explained in U. S. Patent 2,478,926.

The storage v-.=l1eel or rotor 2% located at the lower end of the structure constitutes an integral part of rotating portion of the spindle per so. This rotor is provided with radial passages, one of which is shown indicated at 3t. These communicate with the vertical central bore the spindle. Fhis bore may be considered as a continuous one constituted of the sum of the individual central bores of the component parts of structure when fitted together in non leaking fashion. Ihus, a bore 35 extends through the bearing sup-port structure at the lower end; bore coin :runicates with the bore i i of the member ii through agency of a small air chamber which perijts connecting the oole iii the rotating portion of the spindle with SS and of the stationary portion. The bore ill in turn connects with the bore 32 in portion it of the trusts-conical member it. Since the spring ill, spacer magnet shims 25 and insert it are all con trally bored and are disposed as a prolongation of the bore 32, it is apparent from the foregoing that a continuous, nonleaking ir flow is thus provided which connects the yarn entry aperture at the top in insert 2! with the outlets of p ssages in rotor of the row or re differen ial on the t o s s the which manifests itself, practically speaking, as a suction exerted against the bottom of the dish which urges down against the member 25. The yarn,

s drawn from convo- The yarn approaches of the peel the insert r einber ing i in an of 360 and is drawn between top of member El and the and he stein where succeed- Cu. the yarn :nove bodily about said stem and ur e the out of its ordinarily coaxial alignment with the bore. This movement of the yarn produces continuous notation of the disk. As yarn passes between the tensioning 2ft and storage wheel or rotor 29 it is given one twist for each revolution of the spindle and as the yarn in the balloon between the rotor and the gathering eye (not shown) at point 5'5, it is given a sim lar twist for each rotation of the spindle. The yarn therefore has a two-for-one .st imparted progressively to it as it passes from the package it to the tal-2e-up device. Zhe tel s on exerted on the yarn by the serves to a ain a proper yarn balloon. The rotational tiltln or nutation or the disk he surface of insert 22 permits air to enter this point and to be drawn through the spindle by one action of the rotor 28.

Inasmuch as th rotational speed of such spin- 1 ccurately controlled, the iiow of air produced in such a spindle constant factor and can likewise be accurately controlled, as by means of apertures, bleeder passages, adjusting screws, needle valves or other means suitable for regulating the fiow or air. An embodiment of a simple and preferred method is shown in Figs. 1 and 2 of the drawing.

The lower portion of the member ii is provided with apertures 38 which connect the interior chamber of the spindle with the central air flow bore thereof preferably where the bore of the bearing support structure adjoins the bore of the member l? and Where the small bore connecting chamber Al? is provided as hereinbefore mentioned. Such apertures however may be located at any convenient place along the central air-flow bore of the spindle and used for modifying the flow of air passing through said bore. When these passages are open, air drawn through the yarn package I ii and its fora-ruinous or perfo rated spool i! as well as beneath the edges to where the package is supported on the spindle, enters the air stream passing through the cen tral bore. The how of air through the latter can therefore be modified. for a given set of operat ing conditions by closing or opening many of the apertu es as necessary. This can be effected by inserting removable plugs such as screws iii into certain of the apertures 33 and leaving others open. Preferably such screws should be of a type requiring special tools for their insertion and removal so as to prevent tan1- poring by unauthorized personnel and consequent improper performance of the spindle. In lieu of screws, however, adjustable cocks, bleeder valves, needle valves or other means may be provided, or parts of the interior of spindle assembly may be provided with apertures adapted to be aligned or obturated relative rotation of the par ts.

The magnetic means located at the top or" the spindle for controlling the tension-excl action of the dish 22 may be dispensed with in certain cases removing the magnet 25 and using air fiow alone for effecting the tensioning. In other cases both of these control means y be used simul aneously. In still other cases the magnetic tension control means be alonein the manner recited in U. S. i atent No. 2%8526, in which case of course all of the apertures s should be left open so as to weaken the air passing through the bore sufficiently to prevent it from acting on the disk.

In the illustrative embodiment shown" in the drawing" the continuous p "sage which connects the yarn entry aperture in nernber 2i with the storage wheel or rotor serves for conveying both as well as yarn. However, se'oarate passages may be provided for both the air and yarn and these may be coaxially or concentrically arranged or disposed separately of each other.

The arrangement herein disclserves as a means for regulating the yarn tension in proportion to the spindle speed. As the spindle speed increases, the centrifugal pull of the yarn leaving the rotor increases. The increase in speed of the rotor in turn produces a stronger flow or" air and conseduently greater suction against the bottom of the tensioning disk. The increased centrifugal pull of the yarn would therefore be automa ically compensated by the increased amount of tension produced by the greater of suction acting on the disk.

What is claimed is:

1. In a double twist spindle wherein yarn enters at the top, passes downwardly therein emerges from a passage in a storage wheel at the bottom of said spindle and wherein a disk-like tensioning member bears as a weight against the yarn as it enters the spindle and wherein the rotation of said. storage wheel produces a flow of air through said spindle, the improvement comprising the provision of a continuous non-leaking passage in said spindle between the yarn entry point at the top and said storage wheel for guiding said flow of air, said disk-like member being disposed in the path of said flow of air and serving to restrict said flow whereby to produce a pressure differential on the two sides of said disk-like member, said pressure differential acting as a suction against the bottom of said disklike member to supplement the tension exerted by the weight of said disk-like member on said yarn.

2. In a double twist spindle wherein yarn enters at the top, passes downwardly therein and emerges from a passage in a storage wheel at the bottom of said spindle and wherein a disk-like tensioning member bears as a weight against the yarn as it enters the spindle and wherein the rotation of said storage wheel produces a flow of air through said spindle, the improvement comprising the provision of a continuous non-leaking passage in said spindle between the yarn entry point at the top and said storage wheel for guiding said flow of air, said disk-like member being disposed in the path of said flow of air and serving to restrict said flow whereby to produce a pressure differential on the two sides of said disklike member, said pressure differential acting as a suction against the bottom of said disk-like member to supplement the tension exerted by the weight of said disk-like member on said yarn and means associated with said spindle and adapted to regulate said flow of air and control the pressure differential prevailing at said disk-like member.

3. A twisting spindle including in combination a high speed rotating member at one portion thereof adapted by its rotation to produce a flow of air, means at another portion of said spindle for tensioning yarn, thread, or the like undergoing twist thereon, and means including a conduit connecting said rotating member with said tensioning means to actuate said tensioning means by the air flowing through said conduit.

4. A hollow twisting spindle including in combination a rotating storage wheel, a yarn conducting passage within said storage wheel terminating in a peripheral opening, said storage wheel serving by its rotation to pull a flow of air through said spindle, a yarn package supporting structure carried in non-rotating fashion by said spindle, an entry port on said structure for the inlet of yarn and air, a continuous passage connecting said port with said storage wheel for guiding said yarn to said storage wheel, said last mentioned passage being also non-leaking to guide said flow of air from said entry port to said storage wheel to insure a fiow or air through said last mentioned passage, means for tensioning yarn entering said port, said means being constituted as a disk-like member reposing loosely on said entry port, said disk-like member being pressed against the yarn by the pressure differential acting on said disk-like member and produced by the air flow drawn through said last mentioned passage by the rotation of said storage wheel.

5. In a twisting spindle wherein yarn enters at an aperture at the top, passes downwardly therein and emerges from a passage in a storage wheel at the bottom of said spindle and wherein a disklike tensioning member bears against the yarn as it enters the spindle and wherein the rotation of said storage wheel produces a flow of air through said spindle, the improvement comprising the provision of a continuous passage between said top and said storage wheel for guiding said yarn from said aperture at said top to said storage wheel, said disk-like member being disposed in the path of said flow of air and serving to restrict the flow of air through said passage to produce a pressure difierential on the two sides of said disklike member, said pressure differential acting as a suction against the bottom of said disk-like member to supplement the tension exerted by said disk-like member on said yarn and an auX- illiary air passage connected to said continuous passage and adapted to regulate said flow of air and control the pressure differential prevailing at said disk-like member.

6. In a twister a spindle having a longitudinal thread passage therethrough, means to rotate the spindle at high speed, means including a loosely mounted closure affording thread access to one end of the spindle, said closure functioning to impart drag to the thread, means responsive to rotation of the spindle to create a suction within the spindle and means for applying said suction to said closure means to affect the magnitude of the drag imparted thereby.

'7. In a twister a hollow spindle having a longitudinal thread passage therethrough, means to rotate the spindle at high speed, means including a loosely mounted closure affording thread access to one end of the spindle, said closure functioning to impart drag to the thread, means responsive to rotation of the spindle to create a suction within the spindle acting on said closure to affect the magnitude of the drag imparted thereby and means to modify the suction exerted against said closure by said suction creating means,

8. In a twister a spindle having a longitudinal thread passage therethrough, means to rotate the spindle at high speed, means including a loosely mounted closure affording thread access to one end of the spindle, said closure functioning to impart drag to the thread, magnetic means urgins said closure to drag imparting position, means responsive to rotation of the spindle to create a suction within the spindle and means for applying said suction to said closure means to augment the magnitude of the drag imparted thereby.

9. In a twister a hollow spindle having a longitudinal thread passage therethrough, means to rotate the spindle at high speed, means including a loosely mounted closure affording thread access to one end of the spindle, said closure functioning to impart drag to the thread, magnetic means urging said closure to drag imparting position. means responsive to rotation of the spindle to create a suction within the spindle acting on said closure to augment the magnitude of the drag imparted thereby and means to modify the suction exerted against said closure by said suction creating means.

CHADWICK B. KINGSBURY.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,445,721 Bartholomew July 20, 1948 2,478,926 Kingsbury Aug. 16, 1949 2,559,735 Roberts July 10, 1951 

